1. Field of the Invention
The invention relates to the field of remote audio/visual surveillance, and more particularly to such a system that is compact enough to be carried in a vehicle, such as a patrol car, and at the same time is capable of recording high-resolution video at high frame rates.
2. Statement of the Problem
Audio/visual surveillance systems that are sufficiently compact to be carried in a vehicle, such as a police or patrol car, are well known. These systems generally involve recording audio and visual information on a local recording system in the vehicle, transmitting the audio and visual information to a central command facility for review and/or recording, or combinations of the foregoing. See U.S. Pat. No. 6,037,977 issued May 14, 2000 to Roger Peterson. These systems also often include the acquiring and storing of location information, e.g., the geographical position of the patrol car. See U.S. Pat. No. 4,152,693 issued May 1, 1979 to Ashworth, Jr. These systems have been developed in response to the need for rapidly informing central command facilities, such as police headquarters, of emergency situations and the audio and visual details thereof, and the need for obtaining and preserving audio and visual evidence of crimes, emergencies, and other events that involve police action or participation. For example, to successfully prosecute an individual accused of a crime, the law of the United States of America requires that due process be shown. Audio and visual records can be of critical assistance in proving probable cause for stopping or arrest, and other due process elements.
Audio/video surveillance inherently involves a problem of data transmission and storage, because video data files are generally very large and surveillance must occur for significant periods of time, often days or weeks. Generally, this is addressed in surveillance systems by either saving only a few video frames per second, by storing frames for only a short time and then recycling the storage medium by recording over the previously stored data, or by storing or transmitting only portions of the surveillance data. See, for example, U.S. Pat. No. RE37,508 issued Jan. 15, 2002 to Taylor et al., U.S. Pat. No. 6,211,907 issued Apr. 3, 2001 to Scaman et al., and U.S. Pat. No. 6,456,321 issued Sep. 24, 2002 to Ito, et al. A common solution to the capacity problem is to put the control of the recording devices at the fingertips of the police officers and/or headquarters and have them record only when it is required. See U.S. Pat. No. 6,037,977 referenced above. Surveillance systems also inherently require a system for rapid retrieval of data, and for this reason most state-of-the-art systems data is stored on hard drives or other systems permitting random access. See, for example, U.S. Pat. No. 5,689,442 issued Nov. 18, 1997 to Swanson et al. However, hard drives are fragile if handled improperly, and downloading them without removing them takes so much time that it is unlikely to be done.
Audio/visual surveillance systems are employed in tens of thousands of patrol cars today. State-of-the-art systems, such as the device disclosed in the U.S. Pat. No. 6,037,977 patent mentioned above, give the police officer great flexibility with the multiple cameras and audio sources at his or her disposal. They include the latest technologies, including wireless transmitters, miniature cameras, removable hard drives, and geographical locators. Yet, the goal of having prompt communications with the officers in emergencies and reliable audio and visual evidence for use in court remains elusive. Often, in emergencies, police officers are responding to the situation and do not have time to activate the recording equipment. In most instances, due process evidence is not available because, by the time the systems are turned on, the probable cause evidence has come and gone. Even when the systems have been turned on, the resolution is often so poor that it either is useless or it takes a large amount of computer processing to enhance it to make it useable, or the hazards of police work combined with the fragility of high tech systems causes data to be lost.
Accordingly, there is a need in the art for a patrol car surveillance system that provides high resolution in a compact, rugged, and reliable system that stores sufficient data so that there is a high probability that all due process and other evidentiary data is captured.